"The Vampire Diaries" Season 5 returned with Episode 18 titled "Resident Evil" introducing the new villain character, Markos (Raffi Barsoumian). The brand new episode revealed his connection to the doppelgangers Stefan (Paul Wesley) and Elena (Nina Dobrev) as well as his plan with the Travellers at Mystic Falls and the effect of his return to the Other Side.

Spoiler Alert: This feature contains major spoilers on "The Vampire Diaries" Season 5, Episode 18 "Resident Evil." The doppelganger connection between Stefan and Elena began through visions and Caroline (Candice Accola) initially thinks Elena is just acting strange because of her breakup with Damon (Ian Somerhalder).

However, Caroline declared that there is something seriously wrong after receiving a phone call from Stefan who admitted that he is also having romantic visions with Elena. Bonnie (Kat Graham), who was having a hard time getting in touch with boyfriend Jeremy (Steven R McQueen), got a visit from her grandmother to warn about the trouble on the Other Side.

Liv (Penelope Mitchell) works with the "Three Stooges" Tyler (Michael Trevino), Matt (Zach Roerig) and Jeremy to fulfill her plan of getting rid of the Travellers. Unfortunately, the Travellers are already on the move in taking over Mystic Falls as they become Passengers in the body of some residents and one of them happened to be Caroline's mom, Sheriff Elizabeth Forbes (Marguerite MacIntyre).

Caroline told Damon about Elena's doppelganger situation and the Salvatore vampire wants to find a witch and find out what exactly is going on. Luke Parker (Chris Brochu) showed up at the Salvatore mansion to inform the gang that Markos' return from the Other Side is the reason behind Elena and Stefan's romantic visions and it means that the Travellers and their leader is near.

The Passenger in Sheriff Forbes' body stabbed Matt on the neck temporarily killing him, thanks to the Gilbert ring on his finger that can bring him back to life. Matt goes through Bonnie, the Anchor, to see what it is like on the Other Side and the familiar face that Matt sees comes from the Original vampire Kol Mikaelson (Nathaniel Buzolic).

Matt got reunited with his sister Vicki (Kayla Ewell) on the Other Side but she also warned her brother that things are not going well. Then, the Other Side started to shake and Vicki got snatched someplace else probably where Katherine Pierce (Nina Dobrev) was taken. Kol Mikaelson told Matt that he must remember what happened on the Other Side and tell everyone about the problem.

Elena had another vision of Stefan proposing to her while talking to Damon. The vision revealed an address and Elena thinks they can find Markos there.

Damon and Enzo head to the address and finally meet the reason why Stefan and Elena are having visions of each other. Markos invited Damon for a walk to talk about the spell that he cast over a thousand years ago involving doppelgangers.

According to Markos, Silas (Paul Wesley) and Qetsiyah (Janina Gavankar) cast the immortality spell and it caused the division between the witches and the Travellers community. The witches then cast a spell that prevents the Travellers from living together in numbers and find out how powerful they are but the doppelganger blood can break that spell with the loophole of inhabiting the bodies of others in order to get together without being noticed.

Markos decided to cast a spell with the help of his Travellers that bring an end to the visions of Stefan and Elena. The ex-lovers both agreed that their doppelganger connection may be over but they will always love each other.

Elena and Damon have another grownup talk but it did not end well. Elena told Damon that she still wants him in her life but the Salvatore vampire bluntly told her that he does not want to be her friend, see her, look at her, hear her voice or talk to her so Elena just agreed and walked out of the room looking hurt.

The twist in this episode was revealed in the ending scene where Tyler assured Caroline over the phone that he has everything handled when it comes to the Travellers but it turns out a Passenger inhabits his body. The possessed Tyler, who managed to acquire the last Travellers' knife, hands it over to Markos and the Travellers' leader destroyed the only weapon left.

"The Vampire Diaries" Season 5 will return with Episode 19 titled "Man on Fire" on Thursday night, April 24, at 8 pm ET on the CW Network.